Methods, data and software

Abstract

Population projections are today mostly based on the so-called ‘cohort component method’. This method was developed in the 1930s and 1940s and has not been substantially changed since then. It allows for the projection of populations by age and sex. For this purpose, the population that should be projected is subdivided by sex and into age groups of equal size. The age groups can cover 5 or 10 ages, but also projections of single-year age groups are possible. Such a single-year disaggregation will be used in this study. Only the oldest male and female age groups are of a bigger size as they are open-ended, i.e. they include all persons aged 95 and older. Each of the age- and sex-specific subgroups of the population is separately projected into the future.